Data recording method and apparatus, data reproducing method and apparatus, and data recording and/or reproducing system

ABSTRACT

Even though data transmitted between a data processing apparatus and disc recording and/or reproducing apparatus is monitored, copying the data is effectively prevented and the data can be protected. A write ID generator  20  of a disc recording and/or reproducing apparatus  10  generates independent write ID for each recording of data, and transmits the write ID to an encryptor  102  of a data processing apparatus  100 . The encryptor  102  encrypts contents ID to be used for key information for encrypted contents data and data control information to restrict or prohibit copy by the use of an encrypting key based on the write ID. The encrypted data are transmitted to an encryptor  24  of the disc recording and/or reproducing apparatus  10  via an I/F  101  and I/F  19 , and encrypted along with the write ID by the use of an encrypting key based on disc ID, and recorded to a disc  30.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a data recording method andapparatus, a data reproducing method and apparatus, and a data recordingand/or reproducing system, and particularly to a data recording methodand apparatus, a data reproducing method and apparatus, and a datarecording and/or reproducing system to prevent illegal copy of datarecorded on a disc-shaped recording medium.

[0003] 2. Description of Related Art

[0004] Occasionally, copying data such as digital contents data recordedon a disc-shaped recording medium etc. to another recording medium isnot restricted. On the other hand, such copying is sometimes restrictedor completely prohibited so as not to infringe copyright of data. Incase copying data is required to be restricted or prohibited, somecountermeasures have to be taken. The contents data are, for example,music, image, program, and text data. Identification information (ID)has been used to encrypt contents data or contents keys so as to preventcopying data recorded on the disc-shaped recording medium etc.

[0005] In case a data processing unit for processing contents data to berecorded and a data recording unit for recording data to a recordingmedium are mounted in the same apparatus, printed board, or chip, andthose units are connected by their interfaces which does not output datato outside thereof, copying data can be prevented.

[0006] On the other hand, in case the data processing unit and datarecording unit are mounted in different apparatuses and thoseapparatuses are connected by their general interfaces, data transmittedvia those interfaces can be taken out from those apparatuses, whichenables copying data.

[0007] Even though the data processing unit and data recording unit aremounted in the same apparatus or substrate, copying data becomespossible by monitoring data transmitted between those units via a dataline connecting them.

SUMMARY OF THE INVENTION

[0008] It is therefore an object of the present invention to overcomethe above-mentioned drawbacks by providing a data recording apparatus, adata reproducing apparatus, and a data recording and/or reproducingsystem, which is configured such that, even though the data transmittedbetween a data processing unit and data recording unit is monitored, themonitored data can hardly be read, and thus can prevent copy of data andeffectively protect data.

[0009] It is another object of the present invention to provide a datarecording method and a data reproducing method to implement the datarecording apparatus and data reproducing apparatus.

[0010] According to the present invention, when recording digital datato a recording medium,

[0011] independent write identification information is generated foreach recording of the digital data,

[0012] data identification information of the digital data and datacontrol information are encrypted by the use of the write identificationinformation, and

[0013] at least the encrypted data identification information and datacontrol information, and the write identification information arerecorded to the recording medium.

[0014] According to the present invention, there is provided a datarecording and/or reproducing system which has a data processingapparatus for encrypting data identification information of digital dataand data control information, and a data recording and/or reproducingapparatus for recording the encrypted data identification informationand data control information from the data processing apparatus to arecording medium,

[0015] wherein the data recording and/or reproducing apparatus has meansfor generating independent write identification information for eachrecording of the digital data, and means for recording the encrypteddata from the data processing apparatus and write identificationinformation to the recording medium, and

[0016] wherein the data processing apparatus encrypts the dataidentification information of the digital data and data controlinformation by the use of the write identification information from thedata recording and/or reproducing apparatus, and transmits the encrypteddata to the data recording and/or reproducing apparatus.

[0017] The digital data is encrypted by the data identificationinformation. The encrypted data identification information of thedigital data and data control information, and the write identificationinformation are encrypted by the use of recording medium identificationinformation peculiar to the recording medium, and recorded to therecording medium along with the encrypted digital data.

[0018] The encrypted data identification information and data controlinformation, and the write identification information recorded on therecording medium are read, and the encrypted data identificationinformation and data control information are decrypted by the use of thewrite identification information.

[0019] According to the present invention, the independent writeidentification information is generated for each recording of thedigital data, and the data identification information of the digitaldata and data control information are encrypted by the use of thegenerated write identification information, and at least the encrypteddata identification information and data control information, and thewrite identification information are recorded to the recording medium.So, encrypting by the use of the recording medium identificationinformation peculiar to the recording medium is performed for eachrecording of the digital data. Thus, the data identification informationcannot be decrypted even though the reproduced data from the recordingmedium is copied, which can prevent copying data.

[0020] The digital data is encrypted by the data identificationinformation. Accordingly, the encrypted contents data cannot bedecrypted as long as the data identification information cannot bedecrypted.

[0021] When the data processing unit for encrypting the digital data anddata recording unit for recording data to the recording medium aremounted separately, the data identification information cannot bedecrypted even though the data transmitted between the data processingunit and data recording unit is monitored, which can prevent copyingdata.

[0022] These objects and other objects, features and advantages of thepresent intention will become more apparent from the following detaileddescription of the preferred embodiments of the present invention whentaken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0023]FIG. 1 shows a block diagram of a disc recording and/orreproducing apparatus and data processing apparatus employing thepresent invention.

[0024]FIG. 2 shows a block diagram for explaining the case in which theencrypted data is recorded by a disc recording and/or reproducingapparatus and reproduced by another disc recording and/or reproducingapparatus.

[0025]FIG. 3 shows a block diagram for explaining the case in whichencrypted data recorded on a disc is copied to another disc and thecopied encrypted data is reproduced.

[0026]FIG. 4 shows a block diagram for explaining the case in which thewrite identification information is transmitted without being encrypted.

[0027]FIG. 5 shows a block diagram for explaining the case in which thewrite identification information is encrypted and transmitted from thedisc recording and/or reproducing apparatus to the data processingapparatus, and the encrypted data identification information and datacontrol information are encrypted and transmitted from the dataprocessing apparatus to the disc recording and/or reproducing apparatus.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0028] The data recording method and apparatus, data reproducing methodand apparatus, and data recording and/or reproducing system according tothe present invention will further be described below with reference tothe accompanying drawings.

[0029]FIG. 1 shows a disc recording and/or reproducing apparatus 10 as adata recording apparatus according to the present invention, and a dataprocessing apparatus 100 which may be a personal computer connectedthereto.

[0030] The disc recording and/or reproducing apparatus 10 includes aspindle motor 11 to rotate a disc 30 being a removable disc-shapedrecording medium such as a write-once type optical disc, rewritable typemagneto-optical disc, or phase-change type optical disc, an opticalpickup 12 to radiate a laser beam to the disc 30 and receive thereturning laser beam, a laser driver 13 to drive a laser light source,not shown, such as a laser diode of the optical pickup 12, a signaldetector 14 to detect an output signal from the optical pickup 12, amodulator/demodulator 15 to modulate a signal to the laser driver 13 anddemodulate a signal sent from the signal detector 14, a buffer memory 16to temporarily store data, an arbitrator 17, an ECC (Error CorrectionCode) unit 18 to perform error correction encoding/decoding, an I/F(interface) 19 to transmit/receive data to/from the data processingapparatus 100 such as a personal computer, and a write ID generator 20to generate write ID (identification information) for each recording ofdata. The arbitrator 17 arbitrates data transmitted between the buffermemory 16, and modulator/demodulator 15, ECC unit 18 and I/F 19. Thewrite ID from the write ID generator 20 is sent to the ECC unit 18, andis also sent to the external data processing apparatus 100.

[0031] The spindle motor 11 rotates the disc 30 at a constant linearvelocity or constant angular velocity under the control of a servocircuit, not shown.

[0032] When recording data to the disc 30, a laser light source of theoptical pickup 12 driven by the laser driver 13 radiates a laser beam tothe disc 30 via an optical system such as an objective lens. Whenreproducing data recorded on the disc 30, the laser light source of theoptical pickup 12 radiates a laser beam to the disc 30 via the opticalsystem, and a light-sensitive detector of the optical pickup 12 such asa photodiode receives the returning laser beam reflected and diffractedby the surface of the disc 30, and converts the received laser beam toan electric signal, and outputs the electric signal.

[0033] When recording/reproducing data to/from the disc 30, the opticalpickup 12 performs tracking servo control and focusing servo controlbased on the detected signal of the returning laser beam.

[0034] The write ID generator 20 generates the write ID (identificationinformation) being identification information peculiar to each recording(contents). This write ID is updated every time the data file isrecorded, and is independent identification information for eachrecording operation. The write ID generated for each recording isdifferent from each other, even though the recording operation isperformed in the same disc apparatus and to the same disc. The write IDmay be generated based on random numbers generated by, for example, arandom number generator.

[0035] The disc recording and/or reproducing apparatus 10 furtherincludes an encryptor/authenticator 21. The write ID generated by thewrite ID generator 20 may be transmitted to the data processingapparatus 100 without being processed, or may be encrypted by theencryptor/authenticator 21 and transmitted to the data processingapparatus 100, if necessary. When the write ID is encrypted andtransmitted to the data processing apparatus 100, theencryptor/authenticator 21 performs j ( ) encryption processing for thewrite ID, and transmits the encrypted write ID to the data processingapparatus 100 via the I/F 19. The encryptor/authenticator 21 alsoperforms mutual authentication with the data processing apparatus 100.

[0036] The disc recording and/or reproducing apparatus 10 furtherincludes a disc ID generator 23 and an encryptor 24. The disc IDgenerator 23 generates disc ID (disc identification information), whichwill be described later, and sends the disc ID to the encryptor 24connected to the ECC unit 18. The write ID (write identificationinformation) from the write ID generator 20 is also sent to theencryptor 24.

[0037] The encryptor 24 performs e ( ) encryption processing and f ( )encryption processing for data to be recorded and the write ID,respectively, by the use of a key based on the disc ID, and sends theencrypted data to the ECC unit 18 via the arbitrator 17 and buffermemory 16. The encryptor 24 also performs e⁻¹ ( ) decryption processingand f⁻¹ ( ) decryption processing for data obtained from the ECC unit 18via the arbitrator 17 and buffer memory 16 by the use of the key basedon the disc ID.

[0038] The data processing apparatus 100, such as a personal computer,which is connected to the disc recording and/or reproducing apparatus10, includes an I/F (interface) 101 to transmit/receive data to/from thedisc recording and/or reproducing apparatus 10, encryptor 102 toencrypt/decrypt data, a data processor 103 to process data in variousmanners, an authenticator 104 to perform mutual authentication with anexternal authentication institution etc., an I/F (interface) 105 totransmit/receive data identification information (contents ID, whichwill be described later) and data control information (for example,control information to restrict or prohibit copy generation) to/from anexternal unit, and an encryptor/authenticator 22 to decrypt theencrypted write ID from the I/F 101 and sends the decrypted write ID tothe encryptor 102. The encryptor/authenticator 22 also performs mutualauthentication with the disc recording and/or reproducing apparatus 10.The data processing apparatus 100 further includes an I/F (interface)106 to receive encrypted contents data from outside, and a decryptor 107to decrypt the encrypted contents data from the I/F 106 by the use ofcontents ID (data identification information). When the authenticationis normally performed by the authenticator 104 and the user is proved tobe authorized, the contents ID is sent from the data processor 103 tothe decryptor 107.

[0039] Referring to FIG. 2, the operation of the disc recording and/orreproducing apparatus 10 and data processing apparatus 100 configured asshown in FIG. 1 will be explained. The data processing apparatus 100,such as a personal computer, connected to the disc recording and/orreproducing apparatus 10 is configured such that encrypted contents IDand control information from the authentication institution or a keydistribution center are supplied thereto via the I/F 105, and encryptedcontents data from a contents distribution center or contents provideris supplied thereto via the I/F 106. When the contents data is “u”,contents ID to be used as a key to encrypt data is “cID”, and encryptingis “c ( )”, the encrypted contents data is represented as “c (u, cID)”.When the control information is “cIN”, and encrypting of the contents ID“cID” and control information “cIN” is “s ( )”, the encrypted contentsID and control information are represented as “s (cID+cIN)”.

[0040]FIG. 2 shows the case in which data recorded on a disc 30_0obtained by recording data from the data processing apparatus 100_0thereto by the disc recording and/or reproducing apparatus 10_0 isreproduced by another disc recording and/or reproducing apparatus 10_1.The encrypted contents data c (u_0, cID_0) and encrypted contents ID andcontrol information s (cID_0+cIN_0) are supplied to the data processingapparatus 100_0.

[0041] The data processing apparatus 100 performs mutual authenticationwith an authentication institution. When the data processing apparatus100 is proved to be authorized, the encrypted contents ID and controlinformation s (cID+cIN) are transmitted thereto. The authorized dataprocessing apparatus 100 can decrypt the s (cID+cIN) and obtain contentsID cID to be used as a key for the encrypted contents data.

[0042] That is, in the example shown in FIG. 2, original contents ID andcontrol information cID_0+cIN_0 before encrypting can be obtained byperforming s⁻¹ ( ) decryption processing for the encrypted contents IDand control information s (cID_0+cIN_0) supplied to the data processingapparatus 100_0. The distributed encrypted contents data c (u_0, cID_0)is controlled by the control information cIN_0. In case the frequency ofcopying contents data is restricted, the control information cIN_0 isconverted to cIN_1 by the data processor 103 when recording the contentsdata. The frequency of copying contents data is restricted or copyingcontents data is prohibited in accordance with the control information.Original contents data u_0 before encrypting can be obtained bydecrypting the encrypted contents data c (u_0, cID_0) by the use of thedecrypted contents ID cID_0.

[0043] The disc recording and/or reproducing apparatus 10_1 of FIG. 2generates updated write ID, for example wID_0, for each recording ofdata, and performs j ( ) encryption processing for the wID_0 and outputsthe encrypted wID_0 to the data processing apparatus 100_0. The dataprocessing apparatus 100_0 of FIG. 2 encrypts the contents ID andconverted control information cID_0+cIN_1 by the use of the write IDwID_0 obtained by decrypting the encrypted write ID j (wID_0) from thedisc recording and/or reproducing apparatus 10_1, and generatesencrypted data v (cID_0+cIN_1, wID_0), and transmits the encrypted datato the disc recording and/or reproducing apparatus 10_1. The encryptedcontents data c (u_0, cID_0) is transmitted to the disc recording and/orreproducing apparatus 10_1 without being processed.

[0044] The disc recording and/or reproducing apparatus 10_1 generatesencrypted data f (wID_0, dID_0) by performing f ( ) encryptionprocessing for the write ID wID_0 generated for this recording by theuse of disc ID dID_0 from the disc ID generator 23 of FIG. 1, andgenerates encrypted data e (v ( ), dID_0) by performing e ( ) encryptionprocessing for the encrypted contents ID and control information v(cID_0+cIN_1, wID_0) by the use of the disc ID dID_0. The v ( ) is theabbreviation for the v (cID_0+cIN_1, wID_0). When performing f ( )encryption processing and e ( ) encryption processing, the disc ID dID_0as well as block ID which is identification information for each blockbeing a recording unit can be used, if necessary. These encrypted data f(wID_0, dID_0) and v (cID_0 +cIN_1, wID 0) are recorded to the disc30_0, and the encrypted contents data c (u_0, cID_0) from the dataprocessing apparatus 100_0 is recorded to the disc 30_0 without beingprocessed. The disc ID dID_0 is recorded to a predetermined region (toc,data recording region, etc.) of the disc 30_0 at the time ofinitialization, shipment, or first recording.

[0045] Next, the case in which data of the disc 30_0 is reproduced bythe disc recording and/or reproducing apparatus 10_1 other than the discrecording and/or reproducing apparatus 10_0 will be explained.

[0046] The disc recording and/or reproducing apparatus 10_1 reproducesthe encrypted data e (v ( ), dID_0) and f (wID_0, dID_0), and theencrypted contents data c (u_0, cID_0) from the disc 30_0, andreproduces the disc ID dID_0 from the predetermined region of the disc30_0. The disc recording and/or reproducing apparatus 10_1 obtains theencrypted contents ID and control information v (cID_0 +cIN_1, wID_0),and the write ID wID_0 by decrypting the reproduced encrypted data e (v( ), dID_0) and f (wID_0, dID_0) by the use of the disc ID dID_0. Thedisc recording and/or reproducing apparatus 10_1 transmits the encryptedcontents data v (u_0, wID_0) to the data processing apparatus 100_1 viathe I/F, and performs j ( ) encryption processing for the write ID wID_0and transmits the encrypted write ID data j (wID_0) to the dataprocessing apparatus 100_1. The encrypted contents data c (u_0, cID_0)is transmitted to the data processing apparatus 100_1 without beingprocessed.

[0047] The data processing apparatus 100_1 performs j⁻¹ ( )decryptionprocessing for the encrypted write ID data j (wID_0) to obtain the writeID wID_0, and takes out the contents ID and control informationcID_0+cIN_1 by decrypting the v (cID_0+cIN_1, wID_0) from the discrecording and/or reproducing apparatus 10_1 by the use of the obtainedwrite ID wID_0. The contents data u_0 can be obtained by decrypting theencrypted contents data v (u_0, wID_0) by the use of the contents IDcID_0. At this time, the decrypting is restricted by the controlinformation cIN_1, or the control information cIN_1 itself is processedto be changed. For example, when the copied contents data u_0 is copiedto another disc again, the control information cIN_1 is changed tocontrol information cIN_2.

[0048] According to the present invention configured as described above,the disc ID dID and write ID wID become unrelated to each other, whichcan prevent the disc ID dID and write ID wID from being taken out tooutside from the disc recording and/or reproducing apparatus 10 and dataprocessing apparatus 100. The disc recording and/or reproducingapparatus 10 does not have to know the v ( ) encryption processing forthe contents ID and control information. The data processing apparatus100 performs the v ( ) encryption processing on its own responsibility.And, the disc recording and/or reproducing apparatus 10 performs the e () encryption processing and f ( ) encryption processing on its ownresponsibility. Thus, the security of the interfaces between the discrecording and/or reproducing apparatus 10 and data processing apparatus100, and that of recording/reproducing data to/from the disc 30 by thedisc recording and/or reproducing apparatus 10 can be independent.

[0049]FIG. 3 shows the case in which disc copy is prevented byencrypting data by the use of the write ID.

[0050] In FIG. 3, the data processing apparatus 100_0, data processingapparatus 100_1, disc recording and/or reproducing apparatus 10_0, anddisc recording and/or reproducing apparatus 10_1 are identical withthose in FIG. 2. So, the elements or parts will be indicated with thesame or similar reference numerals, and the explanation will be omitted.In FIG. 3, the encrypted contents ID and control information v(cID_0+cIN_1, wID_0) and encrypted contents data v (u_0, cID_0) from thedisc recording and/or reproducing apparatus 10_1 are transmitted toanother disc recording and/or reproducing apparatus 10_2 and recorded toanother disc 30_2.

[0051] The disc recording and/or reproducing apparatus 10_1 obtains theencrypted data f (wID_0, dID_0) and e (v ( ), dID_0) by reproducing thedata recorded on disc 30_0, and obtains the encrypted contents ID andcontrol information v (cID_0+cIN_1, wID_0), and the write ID wID_0 bydecrypting the reproduced encrypted data f (wID_0, dID_0) and e (v ( ),dID_0) by the use of the disc ID dID_0 recorded to the predeterminedposition of the disc 30_0. The disc recording and/or reproducingapparatus 10_1 obtains the encrypted contents data c ( ), that is c(u_0, cID_0) by reproducing the data recorded on the disc 30_0. Theencrypted data v (cID_0+cIN_1, wID_0) and encrypted contents data c ( )obtained from the disc recording and/or reproducing apparatus 10_1 aretransmitted to the disc recording and/or reproducing apparatus 10_2without being processed, and recorded to another disc 30_2. The discrecording and/or reproducing apparatus 10_2 generates disc ID dID_2corresponding to the disc 30_2 and records the disc ID dID_2 to apredetermined position of the disc 30_2, and generates write ID wID_2when recording data, and encrypts the write ID wID_2 and encrypted datav (cID_0+cIN_1, wID_0) by the use of a key based on the disc ID dID_2,and records thus obtained encrypted data e (v ( ), dlD_2) and f (wID_2,dID_2) to the disc 30_2.

[0052] When reproducing data recorded on the disc 30_2 by a discrecording and/or reproducing apparatus 10_3, the encrypted data e (v (), dID_2) and f (wID_2, dID_2) recorded on the disc recording and/orreproducing apparatus 10_2 are reproduced and transmitted to a discrecording and/or reproducing apparatus 10_3. The encrypted contents datac ( ) is reproduced from the disc 30_2 and transmitted to the discrecording and/or reproducing apparatus 10_3. The disc recording and/orreproducing apparatus 10_3 reads the disc ID dID_2 recorded on apredetermined position of the disc 30_2, and decrypts the encrypted datae (v ( ), dID_2) and f (wID_2, dID_2) by the use of a key based on thedisc ID dID_2. Thus, the copied encrypted data v (cID_0+cIN_1, wID_0)and write ID wID_2 generated when recording the encrypted data v(cID_0+cIN_1, wID_0) to the disc 30_2 are restored. The encrypted data v(cID_0+cIN_1, wID_0) are transmitted to the data processing apparatus100_3 without being processed. The disc recording and/or reproducingapparatus 10_3 performs j⁻¹ ( )decryption processing for the write IDwID_2, and the encrypted write ID wID_2 is transmitted to the dataprocessing apparatus 100_3. The data processing apparatus 100_3 performsj⁻¹ ( )decryption processing for the encrypted write ID j (wID_2) toobtain the write ID wID_2, and tries to decrypt the encrypted data v(cID_0 +cIN_1, wID_0) from the disc recording and/or reproducingapparatus 10_3 by the use of the write ID wID_2. However, since theencrypted data v (cID_0+cIN_1, wID_0) are encrypted by the use of a keybased on the write ID wID_0, the encrypted data v (cID_0+cIN_1, wID_0)can not be decrypted. Thus, original data, that is contents ID andcontrol information cID_0+cIN_1 can not be obtained.

[0053] That is, the data processing apparatus 100_3 receives the writeID wID_2. On the other hand, the encrypted data v (cID_0+cIN_1, wID_0)are encrypted by the write ID wID_0. Thus, it can be seen that illegalcopy is performed from this disaccord of the write ID. Since theencrypted data v (cID_0+cIN_1, wID_0) can not be decrypted by the writeID wID_2, original contents ID and control information cID_0+cIN_1 cannot be obtained.

[0054] It can be considered that, when performing disc copy, reproduceddata from the disc recording and/or reproducing apparatus 10_1 isrecorded by means of the disc recording and/or reproducing apparatus10_0 which records original data. However, since updated write ID isgenerated, and the write ID is different from the write ID wID_0generated at the time of recording original data. Thus, decrypting cannot be performed either.

[0055]FIG. 4 shows the case in which the write ID is transmitted fromthe disc recording and/or reproducing apparatus 10 to the dataprocessing apparatus 100 without being encrypted. Other than this, theelements or parts will be indicated with the same or similar referencenumerals in FIG. 2. So, the explanation will be omitted.

[0056]FIG. 5 shows the case in which the write ID as well as theencrypted contents ID and control information v (cID_0+cIN_1, wID_0) isencrypted and transmitted between the disc recording and/or reproducingapparatus 10 and data processing apparatus 100.

[0057] That is, when recording data, encrypted data j (wID_0) obtainedby performing j ( )encryption processing for the write ID wID_0generated by the disc recording and/or reproducing apparatus 10_1 istransmitted to the data processing apparatus 100_0. The data processingapparatus 100_0 encrypts the contents ID and control informationcID_0+cIN_1 by the use of the write ID wID_0 obtained by decrypting theencrypted data j (wID_0) to generate the encrypted data v (cID_0+cIN_1,wID_0), and performs j ( ) encryption processing for the encrypted datav (cID_0+cIN_1, wID_0), and transmits the encrypted data to the discrecording and/or reproducing apparatus 10_1.

[0058] When reproducing data, the disc recording and/or reproducingapparatus 10_1 decrypts the encrypted data e (v ( ), dID_0) and f(wID_0, dID_0) obtained by reproducing data recorded on the disc 30_0 bythe use of the disc ID dID_0 reproduced from the disc 30_0 to obtain thewrite ID wID_0 and encrypted data v (cID_0+cIN_1, wID_0), and performs j( )encryption processing for the write ID wID_0 and encrypted data v(cID_0+cIN_1, wID_0), and transmits thus obtained encrypted data j(wID_0) and j (v ( ))to the data processing apparatus 100_0. The dataprocessing apparatus 100_0 performs j⁻¹ ( ) decryption processing forthe encrypted data j (wID_0) and j (v ( ))to obtain the wID_0 and v(cID_0+cIN_1, wID_0).

[0059] In FIG. 5, the elements or parts will be indicated with the sameor similar reference numerals in FIG. 2, and the explanation is omitted.

[0060] The present invention is not restricted to the above-mentionedembodiments. In the embodiments, the data processing unit and discrecording and/or reproducing unit are mounted in independentapparatuses. On the other hand, the data processing unit and discrecording and/or reproducing unit can be mounted in independentsubstrates mounted in the same apparatus, or in independent circuitsmounted in the same substrate. The recording medium is not restricted tothe disc-shaped recording medium, and my be a card-shaped or tape-shapedrecording medium. The user data can be data which is not encrypted, ordata which has already been encrypted by another encrypting key.Furthermore, the write ID as well as recording medium ID (disc ID etc.)peculiar to a recording medium such as a disc, and block ID peculiar toa block (sector, frame, etc.) being a unit for encoding or a unit forrecording. In this case, random number generators for generating thewrite ID, disc ID, and block ID can be common. Various modifications canbe possible without departing from the spirit and scope of the presentinvention.

What is claimed is:
 1. A data recording method for recording digitaldata to a recording medium, comprising the steps of: generatingindependent write identification information for each recording of thedigital data; encrypting data identification information of the digitaldata and data control information by the use of the write identificationinformation; and recording at least the encrypted data identificationinformation and data control information, and the write identificationinformation to the recording medium.
 2. The data recording method as setforth in claim 1 , wherein the digital data is encrypted by the dataidentification information, and the encrypted digital data is recordedto the recording medium along with the encrypted data identificationinformation and data control information, and the write identificationinformation.
 3. The data recording method as set forth in claim 1 ,wherein the data control information includes copy control informationfor the digital data.
 4. The data recording method as set forth in claim1 , wherein the encrypted data identification information and datacontrol information, and the write identification information areencrypted by the use of recording medium identification informationpeculiar to the recording medium and recorded to the recording medium.5. The data recording method as set forth in claim 1 , wherein a dataprocessing unit for encrypting the data identification information anddata control information and a data recording unit for recording data tothe recording medium are mounted separately, and the writeidentification information is generated at the data recording unit, andthe generated write identification information is encrypted andtransmitted to the data processing unit.
 6. A data recording apparatusfor recording digital data to a recording medium, comprising: means forgenerating independent write identification information for eachrecording of the digital data; means for encrypting data identificationinformation of the digital data and data control information by the useof the write identification information; and means for recording atleast the encrypted data identification information and data controlinformation, and the write identification information to the recordingmedium.
 7. The data recording apparatus as set forth in claim 6 ,wherein the digital data is encrypted by the data identificationinformation, and the encrypted digital data is recorded to the recordingmedium along with the encrypted data identification information and datacontrol information, and the write identification information.
 8. Thedata recording apparatus as set forth in claim 6 , wherein the datacontrol information includes copy control information for the digitaldata.
 9. The data recording apparatus as set forth in claim 6 , whereinthe encrypted data identification information and data controlinformation, and the write identification information are encrypted bythe use of recording medium identification information peculiar to therecording medium and recorded to the recording medium.
 10. A datarecording and/or reproducing system which has a data processingapparatus for encrypting data identification information of digital dataand data control information, and a data recording and/or reproducingapparatus for recording the encrypted data identification informationand data control information from the data processing apparatus to arecording medium, wherein the data recording and/or reproducingapparatus has means for generating independent write identificationinformation for each recording of the digital data, and means forrecording the encrypted data from the data processing apparatus andwrite identification information to the recording medium, and whereinthe data processing apparatus encrypts the data identificationinformation of the digital data and data control information by the useof the write identification information from the data recording and/orreproducing apparatus, and transmits the encrypted data to the datarecording and/or reproducing apparatus.
 11. The data recording and/orreproducing system as set forth in claim 10 , wherein the digital datais encrypted by the data identification information, and the datarecording and/or reproducing apparatus records the encrypted digitaldata to the recording medium along with the encrypted dataidentification information and data control information, and the writeidentification information.
 12. The data recording and/or reproducingsystem as set forth in claim 10 , wherein the data control informationincludes copy control information for the digital data.
 13. The datarecording and/or reproducing system as set forth in claim 10 , whereinthe data recording and/or reproducing apparatus encrypts the encrypteddata identification information and data control information from thedata processing apparatus, and the write identification information bythe use of recording medium identification information peculiar to therecording medium, and records the encrypted data to the recordingmedium.
 14. The data recording and/or reproducing system as set forth inclaim 10 , wherein the data recording and/or reproducing apparatusauthenticates the data processing apparatus when transmitting the writeidentification information thereto, and encrypts the writeidentification information and transmits the encrypted data to the dataprocessing apparatus when it is proved to be authorized.
 15. A datareproducing method for reproducing digital data from a recording medium,comprising the steps of: reproducing encrypted data identificationinformation and data control information, and write identificationinformation, which are encrypted by the use of recording mediumidentification information from the recording medium; decrypting theencrypted data identification information and data control informationby the use of the write identification information, and taking out thedata identification information of the digital data and data controlinformation.
 16. The data reproducing method as set forth in claim 15 ,wherein the digital data is encrypted by the data identificationinformation and recorded to the recording medium, and the encrypteddigital data is reproduced from the recording medium along with theencrypted data identification information and data control information,and the write identification information.
 17. The data reproducingmethod as set forth in claim 15 , wherein the encrypted dataidentification information and data control information, and the writeidentification information are encrypted by the use of the recordingmedium identification information peculiar to the recording medium andrecorded to the recording medium, and the recording mediumidentification information is reproduced from the recording medium, andthe data encrypted by the recording medium identification informationare decrypted by the use of the recording medium identificationinformation, and the encrypted data identification information and datacontrol information, and the write identification information are takenout.
 18. The data reproducing method as set forth in claim 15 , whereina data processing unit for encrypting the data identificationinformation and data control information and a data recording unit forrecording data to the recording medium are mounted separately, and thewrite identification information is generated at the data recordingunit, and the generated write identification information is encryptedand transmitted to the data processing unit.
 19. A data reproducingapparatus for reproducing digital data from a recording medium,comprising: means for reproducing encrypted data identificationinformation of the digital data and data control information which areencrypted by the use of independent write identification information foreach recording of the digital data, and the write identificationinformation from the recording medium; means for decrypting theencrypted data identification information and data control informationby the use of the write identification information, and taking out thedata identification information and data control information.
 20. Thedata reproducing apparatus as set forth in claim 19 , wherein thedigital data is encrypted by the data identification information andrecorded to the recording medium, and the encrypted digital data isreproduced from the recording medium along with the encrypted dataidentification information and data control information, and the writeidentification information.
 21. The data reproducing apparatus as setforth in claim 20 , wherein the encrypted data identificationinformation and data control information, and the write identificationinformation are encrypted by the use of the recording mediumidentification information peculiar to the recording medium and recordedto the recording medium, and the recording medium identificationinformation is reproduced from the recording medium, and the dataencrypted by the recording medium identification information aredecrypted by the use of the recording medium identification information,and the encrypted data identification information and data controlinformation, and the write identification information are taken out. 22.A data recording and/or reproducing system which has a data recordingand/or reproducing apparatus for reproducing encrypted data which areencrypted by the use of independent write identification information foreach recording of digital data from a recording medium, and a dataprocessing apparatus for decrypting the encrypted data and taking outdata identification information of the digital data and data controlinformation, wherein the data recording and/or reproducing apparatus hasmeans for reproducing the write identification information and encrypteddata from the recording medium, and means for transmitting thereproduced data to the data processing apparatus, and wherein the dataprocessing apparatus decrypts the encrypted data which are encrypted bythe use of the write identification information from the data recordingand/or reproducing apparatus, and takes out the data identificationinformation of the digital data and data control information.
 23. Thedata recording and/or reproducing system as set forth in claim 22 ,wherein the digital data is encrypted by the data identificationinformation and recorded to the recording medium, and the data recordingand/or reproducing apparatus reproduces the encrypted digital data fromthe recording medium along with the encrypted data identificationinformation and data control information, and the write identificationinformation.
 24. The data recording and/or reproducing system as setforth in claim 22 , wherein the encrypted data identificationinformation and data control information, and the write identificationinformation are encrypted by the use of the recording mediumidentification information peculiar to the recording medium and recordedto the recording medium, and the recording medium identificationinformation is reproduced from the recording medium, and the dataencrypted by the recording medium identification information aredecrypted by the use of the recording medium identification information,and the encrypted data identification information and data controlinformation, and the write identification information are taken out.